1. Field of the Invention
The present invention relates to a method of transmitting and receiving data in a wireless access system to ensure privacy and security, and more particularly, to a method of supporting location privacy of a mobile station when the mobile station enters a network.
2. Discussion of the Related Art
Hereinafter, a general encryption scheme will be described in brief.
Encryption means that a transmitter and a receiver intentionally distort data during communication to maintain privacy. A general encryption procedure will be described as follows. The transmitter encrypts plaintext using a specific encryption key to generate a ciphertext. The transmitter transmits the ciphertext to the receiver. The receiver can translate the received ciphertext through decryption. In this way, the transmitter and the receiver can encrypt voice and/or data for privacy of communication between them.
Examples of the encryption scheme include a symmetric key scheme and an asymmetric key scheme.
The symmetric key scheme means that a single key is used for encryption and decryption. A symmetric key algorithm means that the transmitter and the receiver perform encryption and decryption using a single key (shared secret key).
The asymmetric key scheme means that an encryption key, i.e., public key, used for encryption is different from a secret key (or private key) used for decryption and thus the public key is only opened to the public and the secret key is maintained safely. The asymmetric key scheme is based on a public key based structure such as Revest Shamir Adleman (RSA) or a public key encryption mode.
Hereinafter, a general method of performing a network entry procedure from a mobile station to a base station will be described in brief.
The mobile station can acquire synchronization with the base station by scanning a downlink panel of the base station. Also, the mobile station can acquire transmission parameters through an uplink channel descriptor (UCD) message. Accordingly, the mobile station can perform an initial ranging procedure for the base station.
After performing the initial ranging procedure, the mobile station and the base station can perform negotiation of basic capability. The base station can give a right for performing communication to the mobile station by authenticating the mobile station and exchange an encryption key with the mobile station. Thus, the mobile station can perform a registration procedure to the base station.